Microsoft has announced Search Server 2008, a search engine based on SharePoint Server and SQL Server.

There are two editions, a free Express version and a paid for variant (price not yet determined) which supports high availability and load balancing on a server farm.

They will be released in the first half of 2008, and a preview release is available immediately here. Both editions require either Windows Server 2003 or the forthcoming Windows Server 2008. A dedicated machine is not required, though it is recommended for best performance.

Search Server can draw results from a variety of sources, including simple file shares, Lotus Notes databases, and search engines such as Wikipedia that support the Open Search standard. There are also providers for Google and Windows Live, and connectors for FileNET and Documentum.

Microsoft's SharePoint product manager in the UK, Rob Gray, said these releases are aimed at companies not yet using the full Office SharePoint Server, and that any features not yet in SharePoint Server will in due course be folded into the main product. It integrates with Active Directory so that restricted documents do not show up in searches by unauthorised users.

Gray would not be drawn on the question of how many concurrent users the free Express edition will support. "We're doing benchmarking around what a single Express box gives you versus a connection to an external SQL server versus the full-blown search server in a load-balanced configuration," he said. "There are a lot of different architecture options."

So how does Search Server compare to a search appliance from Google, such as Google Mini. Gray said: "You don't have to buy a piece of hardware; it's free; you don't have preset document limits, and we have a richer administration dashboard."

It seems Microsoft's strategy is to give away a bit more of its SharePoint technology in order to entice more organisations to migrate to the full version, and to keep them hooked on Windows and Office. ®

A freelance journalist since 1992, Tim Anderson specialises in programming and internet development topics. He has columns in Personal Computer World and IT Week, and also contributes regularly to The Register. He writes from time to time for other periodicals including Developer Network Journal Online, and Hardcopy.